[Q] How is it possible to brick a phone? topic

I'm kind of expert in the PC/laptop world, but a little rookie in Android and smartphones world. I don't get how a phone can get bricked.

As far as I know, an Android device has internal memory, and a portion of this internal memory is ROM (read-only memory), where the OS/firmware is installed. It's ROM because you don't want to mess around changing things of the OS, because you're not supposed to change things of the OS for the sake of a correct behavior of the phone.

The thing is that if you accidentally mess up something in the OS/firmware, you can, or should be always able to, re-install the OS again and start all over again. I mean, if I delete some Windows files in my PC and completely mess Windows up, I can always turn off the PC, turn it on, go to BIOS menu, boot from a Windows CD and re-install it. No problems at all.

So... where's the BIOS in Android? The recovery menu in Android is like the BIOS in Windows?
Bricking a phone is like damage the software of the hard disk drive (windows) or is it like mess up the BIOS?

Thanks!